[clang] [llvm] [PowerPC][X86] Make cpu id builtins target independent and lower for PPC (PR #68919)

[Nemanja Ivanovic via cfe-commits]

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@@ -2110,6 +2110,66 @@ static bool checkFPMathBuiltinElementType(Sema &S, SourceLocation Loc,
   return false;
 }
 
+/// SemaBuiltinCpuSupports - Handle __builtin_cpu_supports(char *).
+/// This checks that the target supports __builtin_cpu_supports and
+/// that the string argument is constant and valid.
+static bool SemaBuiltinCpuSupports(Sema &S, const TargetInfo &TI,
+                                   const TargetInfo *AuxTI, CallExpr *TheCall) {
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nemanjai wrote:

Turns out this is actually needed. There is a test that builds with `-triple aarch64 -aux-triple x86_64`. I will have to put the AUX target checks back.

https://github.com/llvm/llvm-project/pull/68919